Concrete5 up to and including 8.5.2 allows Unrestricted Upload of File with Dangerous Type such as a .php file via File Manager. It is possible to modify site configuration to upload the PHP file and execute arbitrary commands.
An issue was discovered in tools/conversations/view_ajax.php in Concrete5 before 8.3.0. An unauthenticated user can enumerate comments from all blog posts by POSTing requests to /index.php/tools/required/conversations/view_ajax with incremental 'cnvID' integers.